As humans age, their hearing naturally grows less acute because they begin to lose tiny sensory hairs (pictured, magnified) in their inner ears that convert sound waves into neurological signals. But now scientists have figured out how to genetically-engineer the cells that generate these sensory hairs. This is a boon for people who are losing their hearing, but it could also lead to super-hearing. Add more sensory hairs to an ear that's in good condition, and you might get someone who is more sensitive to sound. PhysOrg has the report:

At birth, humans have about 30,000 hair cells, which can be damaged by infections, ageing, genetic diseases, loud noise or treatment with certain drugs. In most cases, damaged hair cells do not regrow in mature humans. But recent research has kindled hope that nerve deafness may one day be curable. A team of scientists led by John Brigande at the Oregon Health and Science University, in Portland showed that implanting a gene known as Atoh1 into the inner ear of a mouse embryo coaxed non-sensory cells to become hair cells.

Brigande is confident that this technique could be used in humans too, after a reasonable period of testing. What's fascinating is that this research allows scientists to generate sensory hair cells out of other kinds of cells. Which could lead far beyond the "super hearing" idea. What if skin cells on your fingertips were genetically altered to produce these sensory hairs? Would you "hear" in your fingers? Image by Shayne Davidson/Human Molecular Genetics.Growing New Ear Hairs that Can Boost Hearing [PhysOrg]